Uplink and downlink scheduling method, device, equipment, medium and program product

Abstract

The embodiment of the invention provides an uplink and downlink scheduling method and device, equipment, a medium and a program product. The uplink and downlink scheduling method comprises the following steps: calculating round-trip delay information of a satellite and user equipment based on service area information of the satellite; based on the time allocation information and the round-trip delay information, checking whether a first link scheduling moment of the user equipment conflicts with a second link scheduling moment corresponding to the time allocation information; if not, the uplink and downlink are scheduled at the target moment, and the time distribution information is used for representing the moment when the user equipment carries out the scheduling task. By acquiring the service area information of the satellite, calculating the round-trip delay information of the satellite and the user equipment and verifying based on the time allocation information, uplink and downlink scheduling conflicts of the user equipment are avoided, so that the time-frequency resource utilization rate is effectively improved. The resource waste is reduced, the coordination of the uplink and the downlink is optimized, and the overall network efficiency is improved.

Description

Technical Field

[0001] Embodiments of the present invention relate to the field of satellite communication technology, and particularly to an uplink and downlink scheduling method, apparatus, device, medium, and program product. Background Art

[0002] Non-Terrestrial Networks (NTN) extend the coverage of traditional terrestrial cellular networks through non-ground facilities such as satellites, enabling remote areas, the ocean, and the air to enjoy communication services. NTN shows great potential in emergency response, the Internet of Things, and global connectivity.

[0003] Although NTN provides wide-area coverage, its time-frequency resource utilization rate is limited, becoming a key bottleneck restricting performance improvement. Due to the long signal propagation delay (RTT) between satellites and ground terminals, existing scheduling mechanisms are difficult to efficiently coordinate uplink and downlink resources, resulting in resource waste and potential conflicts.

[0004] Therefore, there is an urgent need for an uplink and downlink scheduling method to improve time-frequency resource utilization. Summary of the Invention

[0005] In view of this, embodiments of the present invention provide an uplink and downlink scheduling method. One or more embodiments of the present invention also relate to an uplink and downlink scheduling apparatus, a computing device, a computer-readable storage medium, and a computer program product to solve the technical defects existing in the prior art.

[0006] According to the first aspect of the embodiments of the present invention, an uplink and downlink scheduling method is provided, which is applied to a base station deployed on a satellite, and includes: Calculating the round-trip delay information between the satellite and the user equipment based on the service area information of the satellite; Based on the time allocation information and the round-trip delay information, verifying whether the first link scheduling time of the user equipment conflicts with the second link scheduling time corresponding to the time allocation information, where the first link scheduling time and the second link scheduling time are determined under the constraint of performing link scheduling at the target time; If not, then scheduling the uplink and downlink at the target time, where the time allocation information is used to represent the time when the user equipment performs the scheduling task.

[0007] According to the second aspect of the embodiments of the present invention, an uplink and downlink apparatus is provided, which is applied to a base station deployed on a satellite, and includes: A calculation module configured to calculate the round-trip delay information between the satellite and the user equipment based on the service area information of the satellite; A verification module, configured to verify whether there is a conflict between a first link scheduling time of a user equipment and a second link scheduling time corresponding to time allocation information based on the time allocation information and round-trip delay information, where the first link scheduling time and the second link scheduling time are determined based on the constraint of performing link scheduling at a target time; A scheduling module, configured to, if not, schedule uplink and downlink at the target time, where the time allocation information is used to represent the time when the user equipment performs a scheduling task.

[0008] According to a third aspect of an embodiment of the present invention, there is provided a computing device, including: A memory and a processor; The memory is used to store computer programs / instructions, and the processor is used to execute the computer programs / instructions. When the computer programs / instructions are executed by the processor, the steps of the above uplink and downlink method are implemented.

[0009] According to a fourth aspect of an embodiment of the present invention, there is provided a computer-readable storage medium, which stores computer programs / instructions. When the computer programs / instructions are executed by a processor, the steps of the above uplink and downlink method are implemented.

[0010] According to a fifth aspect of an embodiment of the present invention, there is provided a computer program product, including computer programs / instructions. When the computer programs / instructions are executed by a processor, the steps of the above uplink and downlink method are implemented.

[0011] An embodiment of the present invention realizes calculating round-trip delay information between a satellite and a user equipment based on service area information of the satellite; verifying whether there is a conflict between a first link scheduling time of the user equipment and a second link scheduling time corresponding to the time allocation information based on the time allocation information and the round-trip delay information, where the first link scheduling time and the second link scheduling time are determined based on the constraint of performing link scheduling at a target time; if not, scheduling uplink and downlink at the target time, where the time allocation information is used to represent the time when the user equipment performs a scheduling task. By obtaining the service area information of the satellite, calculating the round-trip delay information between the satellite and the user equipment, and performing verification based on the time allocation information, scheduling conflicts in the uplink and downlink of the user equipment are avoided, ensuring that there will be no conflict with the existing resource allocation of the user equipment when scheduling uplink and downlink at the target time, thereby effectively improving the time-frequency resource utilization rate. Resource waste is reduced, the coordination of the uplink and downlink is optimized, and the overall network efficiency is improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 It is a schematic diagram of a guard interval and an uplink and downlink; Figure 2 It is a schematic diagram of a round-trip delay calculation method provided by an embodiment of the present invention; Figure 3 is a flowchart of an uplink and downlink scheduling method provided by an embodiment of the present invention; Figure 4 is a flowchart of a processing procedure of an uplink and downlink scheduling method provided by an embodiment of the present invention; Figure 5 is a schematic diagram of another round-trip delay calculation method provided by an embodiment of the present invention; Figure 6 is a schematic structural diagram of an uplink and downlink scheduling device provided by an embodiment of the present invention; Figure 7 is a structural block diagram of a computing device provided by an embodiment of the present invention. Detailed implementation manners

[0013] In the following description, many specific details are set forth in order to provide a thorough understanding of the present invention. However, the present invention can be implemented in many other ways different from those described herein, and those skilled in the art can make similar extensions without departing from the connotation of the present invention. Therefore, the present invention is not limited by the specific implementations disclosed below.

[0014] The terms used in one or more embodiments of the present invention are for the purpose of describing specific embodiments only and are not intended to limit one or more embodiments of the present invention. The singular forms "a", "said", and "the" used in one or more embodiments of the present invention and the appended claims are also intended to include the plural forms unless the context clearly dictates otherwise. It should also be understood that the term "and / or" used in one or more embodiments of the present invention refers to and includes any or all possible combinations of one or more of the associated listed items.

[0015] It should be understood that although the terms first, second, etc. may be used in one or more embodiments of the present invention to describe various information, such information should not be limited to these terms. These terms are only used to distinguish the same type of information from each other. For example, without departing from the scope of one or more embodiments of the present invention, the first may also be referred to as the second, and similarly, the second may also be referred to as the first. Depending on the context, the word "if" as used herein may be interpreted as "when" or "while" or "in response to determining".

[0016] In addition, it should be noted that the user information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data for analysis, stored data, displayed data, etc.) involved in one or more embodiments of the present invention are all information and data that have been authorized by the user or fully authorized by all parties. Moreover, the collection, use, and processing of relevant data need to comply with the relevant laws, regulations, and standards of the relevant countries and regions, and corresponding operation entrances are provided for users to choose to authorize or refuse.

[0017] First, the noun terms involved in one or more embodiments of the present invention are explained.

[0018] Non-Terrestrial Network: That is, Non-Terrestrial Network (NTN). A non-terrestrial network refers to a communication network provided through non-ground infrastructure such as satellites and high-altitude platforms (such as drones or balloons), which is used to supplement or expand the coverage of traditional terrestrial networks, especially in scenarios where it is difficult to deploy ground base stations, such as remote areas, the ocean, or disaster areas.

[0019] Terrestrial Network: That is, Terrestrial Network (TN). A terrestrial network refers to a traditional communication network built based on ground infrastructure (such as base stations, optical fibers, and routers, etc.), which is widely used in cities and densely populated areas to provide stable and high-speed communication services.

[0020] User Equipment: That is, User Equipment (UE). User equipment refers to the communication equipment used by end-users, such as mobile phones, tablets, or Internet of Things devices, which are used to access the network and realize communication functions such as voice, data, and video.

[0021] Next Generation NodeB: That is, the next Generation NodeB (gNB). The next generation base station is a key infrastructure in the 5G network, responsible for providing wireless access services to user equipment, supporting higher data rates, lower latency, and broader connection capabilities.

[0022] Frequency Division Duplexing: That is, Frequency Division Duplexing (FDD). Frequency division duplexing is a communication technology that simultaneously transmits uplink and downlink data by using different frequencies to achieve two-way communication, and is suitable for symmetric service scenarios.

[0023] Time Division Duplexing: That is, Time Division Duplexing (TDD). Time division duplexing is a communication technology that allocates different time slots on the same frequency to transmit uplink and downlink data respectively. It is suitable for asymmetric service scenarios and has high flexibility.

[0024] Evolved Universal Terrestrial Radio Access: namely E-UTRA. Evolved Universal Terrestrial Radio Access is the radio access technology in the 4G LTE network, providing higher data rates and lower latency, and is an important foundation for modern mobile communications.

[0025] Guard Period: namely GP. The guard period is the time interval set in a time-division duplex system to avoid interference between the uplink and downlink, and is used to ensure the correct transmission and reception of signals.

[0026] Round-Trip Time: namely RTT. The round-trip time refers to the time required for a signal to travel from the transmitter to the receiver and then back to the transmitter, and is often used to measure the delay performance of a communication link and is an important parameter for optimizing network scheduling.

[0027] Uplink: The uplink is the communication link through which the UE sends data to the base station or satellite, and is used to transmit user requests, uploaded data, or other information. It is the core channel from the terminal to the network in a wireless communication system, and usually issues such as power limitations and interference management need to be considered.

[0028] Downlink: The downlink is the communication link through which the base station or satellite sends data to the UE, and is used to transmit network responses, downloaded data, or other service content. It is the main channel from the network to the terminal in a wireless communication system, and usually resource allocation needs to be optimized to improve transmission efficiency and user experience.

[0029] In the E-UTRA system, FDD adopts a frequency-division duplex communication mode, and the uplink and downlink transmissions use a pair of frequency bands with the same bandwidth, thus avoiding interference between the uplink and downlink.

[0030] In an FDD communication network, the UE also needs to use the corresponding frequency bands to simultaneously transmit uplink and downlink signals. However, for the Ka band (a specific frequency band in the electromagnetic wave spectrum), since the bandwidth of the uplink and downlink frequency bands can reach 400 MHz, ordinary UEs are limited by the antenna processing ability and cannot support simultaneous uplink and downlink transmissions. Therefore, a time-division transmission method for the uplink and downlink is adopted, that is, half-duplex scheduling.

[0031] The half-duplex scheduling UE (HD-UE) adopts a transmission method similar to TDD. However, different from TDD, different frequency bands are used for the uplink and downlink. Therefore, there is no interference between the uplink and downlink on the channel. The only limitation is that this type of UE cannot simultaneously schedule the uplink and downlink channels, while the base station side can simultaneously schedule the uplink and downlink.

[0032] The 5G terrestrial network follows the design concept of TDD. For HD-UE, the base station needs to reserve GP between transmitting downlink signals and receiving uplink signals to avoid the UE from simultaneously scheduling uplink and downlink channels. The time length of GP is related to the cell radius. The larger the cell radius, the longer the RTT for signals to transmit between the base station and the UE, and the longer the time interval that GP needs to reserve. GP needs to be able to cover the RTT and the uplink and downlink handover time of the UE. See Figure 1 as shown in Figure 1 Figure Figure 1 is a schematic diagram of the guard interval and the uplink and downlink links, where DL represents downlink scheduling, UL represents uplink scheduling, and GP is the guard interval.

[0033] Compared with the TN network, in the NTN network, since the UE is far from the satellite, if GP is reserved in the way of the maximum RTT, a long time needs to be reserved without scheduling. For example, for a satellite with an orbital altitude of 600 km, at the edge position of its communication range, the distance from the UE to the satellite can reach 1200 km. At this time, the maximum RTT duration is (because it calculates the round trip and multiplies by 2 times): RTTmax = 2 * 1200 * 103 / 3 * 108 = 8 (ms) According to the protocol, taking the time slot period configuration of 10 ms as an example, if GP reserves 8 ms, data transmission cannot be performed, which greatly limits the air interface transmission efficiency of the NTN network. However, compared with TN, the minimum distance from the UE to the gnb cannot reach 0. Therefore, there is a range for the actual RTT, and GP only needs to cover the RTT within the range, which greatly reduces the duration requirement of GP. Taking the above satellite as an example again, the point closest to the satellite is the sub-satellite point. At this time, the minimum RTT duration is: RTTmin = 2 * 600 * 103 / 3 * 108 = 4 (ms) Therefore, the GP length only needs to cover RTTmax - RTTmin = 4 (ms).

[0034] However, for the NTN network, the GP length can still be optimized under specific conditions. Generally, the coverage range of a satellite is relatively large, and the coverage range of the satellite needs to be divided into multiple signaling wave positions. In this scenario, only the RTT range under one signaling wave position needs to be considered. Taking the radius of the divided signaling wave position as 25 km as an example, see Figure 2 as shown in Figure 2 Figure Figure 2 is a schematic diagram of a round-trip delay calculation method provided by an embodiment of the present invention. S represents the satellite, the circle FGH represents the terrestrial signaling cell, C is the center of the circle (i.e., the wave position center), F and G are any two points on the circle, the chord length is denoted as d, GH is the diameter of the circle passing through point G and is denoted as D, s1 is the transmission distance from the satellite to point G, and s2 is the transmission distance from the satellite to point F.

[0035] RTT difference between the UE at point G and point F:

[0036] Therefore, within the signaling wave position, the GP only needs to cover a time of 2 * 25 * 103 / 3 * 108 = 166 (us). It can be seen that the prior art wastes the uplink and downlink transmission resources.

[0037] To solve the above problems, in the present invention, a method for uplink and downlink link scheduling is provided. The present invention also relates to an uplink and downlink link scheduling device, a computing device, a computer-readable storage medium, and a computer program product, which will be described in detail one by one in the following embodiments.

[0038] See Figure 3 , Figure 3 is a flowchart of a method for uplink and downlink link scheduling provided by an embodiment of the present invention, which specifically includes the following steps.

[0039] Step 302: Calculate the round-trip delay information between the satellite and the user equipment based on the service area information of the satellite.

[0040] Among them, the round-trip delay information refers to the total time of signal transmission between the satellite and the user equipment, including the total time of electromagnetic waves transmitted from the satellite to the user equipment and then from the user equipment to the satellite. The service area information includes the specific geographical area covered by the satellite and its boundary, which can be used to determine the relative distances of users at different positions within the area.

[0041] In practical applications, first, the position data of the satellite and the geographical information of the service area are obtained. These information are usually provided by satellite operators and updated regularly. The system calculates the specific position of the satellite relative to the earth's surface according to the orbital parameters of the satellite. Then, using geographic information system technology, analyze the geographical distribution within the service area to identify the positions of the user equipment near the sub-satellite point and far from the sub-satellite point. For the user equipment near the sub-satellite point, it is located directly below the satellite and has the shortest distance; while for the edge user equipment, it is located at the boundary of the service area and has the farthest distance. The system calculates the distance from each user equipment to the satellite based on these position information, and based on the propagation speed of radio signals (the speed of light), calculates the round-trip delay information. Specifically, the system divides the straight-line distance between the satellite and the user equipment by the speed of light to obtain the one-way delay, and then multiplies it by 2 to get the round-trip delay. For the calculation method in this step, an optional way is to directly use the geometric distance formula for calculation; another optional implementation method is to adopt a more complex model, considering the influence of factors such as atmospheric refraction on signal propagation, so as to obtain more accurate round-trip delay information.

[0042] In a specific embodiment of the present invention, it is assumed that a certain low-earth orbit satellite is providing communication services for its covered service area. The service area is a circular area with a radius of 1000 kilometers. The satellite is currently at a height of 350 kilometers directly above the center of the service area. The system first determines the specific geographical locations of multiple user devices within the service area. For example, one user device is located near the sub-satellite point, and another user device is located far from the sub-satellite point. Based on the three-dimensional coordinates of the satellite and the two-dimensional geographical coordinates of the user devices, the actual distance from each user device to the satellite is calculated through spatial geometric calculations. Subsequently, the system uses the speed of light as a reference to calculate the round-trip delay information. For the user device near the sub-satellite point, the round-trip delay is shorter; while for the edge user device, due to the longer distance, the round-trip delay is longer. All these calculation results are recorded for subsequent scheduling tasks.

[0043] Furthermore, calculating the round-trip delay information between the satellite and the user device based on the service area information of the satellite includes: obtaining the satellite position information, the longitude and latitude information of the center of the service area, and the size parameters of the service area; determining the angular offset of the user device based on the satellite position information, the longitude and latitude information, and the size parameters, where the angular offset is the angle between the position offset of the user device relative to the projection of the center of the service area on the earth's surface and the center of the earth; calculating the transmission distance based on the angular offset and the satellite position information, and calculating the round-trip delay information between the satellite and the user device based on the transmission distance.

[0044] Among them, the satellite position information provides the orbital position of the satellite, while the longitude and latitude information of the center of the service area and the size parameters of the service area describe the specific position and size of the service area.

[0045] In practical applications, the system first obtains the satellite position information, the longitude and latitude information of the center of the service area, and the size parameters of the service area. These information are usually provided by the satellite operator and updated regularly. Based on these data, the system calculates the angular offset of the user device relative to the center of the service area, that is, the angle between the position offset of the user device projected on the earth's surface and the center of the earth. The calculation of the angular offset takes into account the relative position relationship between the actual geographical location of the user device and the center point of the service area. Then, the system uses the satellite position information and the angular offset to calculate the transmission distance between the user device and the satellite. Specifically, the system derives the transmission distance based on factors such as the height of the satellite, the relative position of the user device, and the radius of the earth. Based on the transmission distance, the system further calculates the round-trip delay information. For the calculation method in the steps, an optional way is to directly use the geometric distance formula for calculation; another optional implementation method is to adopt a more complex model, considering the influence of factors such as atmospheric refraction on signal propagation, so as to obtain more accurate round-trip delay information.

[0046] Within the signaling wave position covered by each satellite, the system calculates the transmission delay range within the wave position. First, the system determines the distance between the satellite and the center point of the service area based on the position information of the satellite and the longitude and latitude information of the center point of the service area. Then, the system calculates the transmission distances of the edge points of the wave position to determine the minimum and maximum delays. The minimum delay corresponds to the center point of the wave position, while the maximum delay corresponds to the edge point of the wave position. By analyzing the geometric relationship among the satellite, the center of the earth, and the center point of the service area, the system can deduce the transmission distances of the edge points of the wave position and calculate the round-trip delay (RTT) range accordingly. To cope with the RTT changes caused by satellite movement, the system converts the RTT range into scheduled time slot values and expands one time slot forward and backward respectively to ensure the flexibility and reliability of scheduling.

[0047] In a specific embodiment of the present invention, it is assumed that a certain low-earth orbit satellite is providing communication services for the service area it covers. The service area is a circular area with a radius of 1000 kilometers. The satellite is currently at a height of 350 kilometers directly above the center of the service area. The system first determines the specific geographical locations of multiple user devices within the service area. For example, one user device is located at the center of the wave position, and another user device is located at the edge of the wave position. Based on the three-dimensional coordinates of the satellite and the two-dimensional geographical coordinates of the user devices, the system calculates the actual distances from each user device to the satellite through spatial geometric calculations. Subsequently, the system uses the speed of light as a reference to calculate the round-trip delay information. For the user device at the center of the wave position, the round-trip delay is shorter; while for the user device at the edge of the wave position, due to the longer distance, the round-trip delay is longer. All these calculation results are recorded for subsequent scheduling tasks. The system also considers the impact of satellite movement, converts the RTT range into scheduling time slots, and appropriately expands the time slot range to ensure the accuracy and flexibility of scheduling.

[0048] Based on this, through the accurate calculation of satellite and service area information, the system can accurately determine the round-trip delays between each user device and the satellite. This accurate delay information provides key data support for subsequent resource allocation, enabling the system to reasonably arrange the scheduling of uplink and downlink links while taking into account the significant propagation delay differences among different user devices, thereby ensuring the reliability and efficiency of communication.

[0049] Step 304: Based on the time allocation information and the round-trip delay information, verify whether the first link scheduling time of the user device conflicts with the second link scheduling time corresponding to the time allocation information, where the first link scheduling time and the second link scheduling time are determined under the constraint of performing link scheduling at the target time.

[0050] Among them, the time allocation information refers to the specific time-frequency resources allocated by the base station for the user equipment and their scheduling moments, and the round-trip delay information refers to the total signal transmission time between the satellite and the user equipment. The first link scheduling moment is the moment of the scheduling task (uplink or downlink) of the user equipment corresponding to the current moment at the base station side (UE side), and the second link scheduling moment is the moment of the scheduling task (downlink or uplink) of the user equipment corresponding to the time allocation information at the base station side (UE side). Verifying whether these two scheduling moments conflict is to ensure that there is no interference between the uplink and downlink at the user equipment side.

[0051] In practical applications, the system first obtains the time allocation information and the round-trip delay information at the base station side. The time allocation information includes the specific scheduling tasks (such as uplink or downlink) of each user equipment and their corresponding scheduling moments. The system calculates the actual scheduling moments at the user equipment side considering the impact of the round-trip delay based on this information. For each user equipment, the system determines its first link scheduling moment, that is, the moment of the scheduling task of the user equipment corresponding to the current moment at the base station side (UE side), and determines the second link scheduling moment based on the time allocation information, that is, the moment of the other link task allocated to the user equipment by the base station side (UE side). Next, the system compares these two scheduling moments to check whether there is overlap or conflict. Specifically, the system adds the round-trip delay to the first link scheduling moment to obtain the actual reception or transmission moment at the user equipment side and compares it with the second link scheduling moment. If there is overlap between the two moments, it is considered that the scheduling task conflicts. For the verification method in the step, an optional way is to introduce a guard interval and insert a time period without data transmission between the two scheduling moments at the UE side to avoid potential conflicts.

[0052] In a specific embodiment of the present invention, assume that the base station allocates a downlink task to a certain user equipment at time T1, the scheduling moment is T1, and plans to allocate an uplink task at the same time, the scheduling moment is T2. The system first calculates the actual moments of these two scheduling moments at the user equipment side considering the impact of the round-trip delay. For example, the transmission delay of the downlink is 50 milliseconds, and the transmission delay of the uplink is also 50 milliseconds. The system adds the downlink delay to the scheduling moment T1 at the base station side to obtain the actual reception moment T1' at the user equipment side, and subtracts the uplink delay from T2 to obtain the actual transmission moment T2' at the user equipment side. Then, the system compares T1' and T2' to check whether there is overlap. If it is found that there is overlap between T1' and T2', it means that they conflict. If the value of T1 plus the round-trip delay is denoted as T1'', and the value of T2 minus the round-trip delay is denoted as T2'', then comparing T1’ and T2’ is equivalent to comparing whether T1'' conflicts with T2, or comparing whether T1 conflicts with T2''.

[0053] Further, the time allocation information is the time allocation information for the uplink, the first link scheduling time is the time when the user equipment receives the downlink, and the second link scheduling time is the time when the user equipment initiates the uplink; based on the time allocation information and the round-trip delay information, verifying whether there is a conflict between the first link scheduling time of the user equipment and the second link scheduling time corresponding to the time allocation information includes: obtaining the time allocation information for the uplink; based on the time allocation information for the uplink and the round-trip delay information, verifying whether there is a conflict between the time when the user equipment receives the downlink corresponding to the target time and the time when the user equipment initiates the uplink; correspondingly, if not, scheduling the uplink and downlink at the target time, including: if not, scheduling the downlink at the target time.

[0054] In practical applications, the system first obtains the time allocation information and the round-trip delay information on the base station side. Assume that the current time slot is n and the round-trip delay is K. The time allocation information includes the specific scheduling tasks (such as uplink or downlink) of each user equipment and their corresponding scheduling times. The system calculates the actual scheduling times on the user equipment side considering the impact of the round-trip delay. Specifically, the system sets the first link scheduling time (i.e., the time when the user equipment receives the downlink) as n + K / 2, because it takes half of the round-trip delay time for the base station to send downlink data to the user equipment for reception. At the same time, the second link scheduling time (i.e., the time when the user equipment initiates the uplink) is set as the time when the base station receives the uplink minus half of the round-trip delay time, that is, the time when the base station receives the uplink - K / 2. To verify whether there is a conflict, the system compares these two times to check whether there is an overlap. For example, the system will verify whether there is a conflict between n + K and the time when the base station receives the uplink. If there is an overlap between the two times, it is considered that there is a conflict in the scheduling tasks on the UE side; if there is no conflict, the uplink or downlink can be scheduled at the target time. For the verification method in the step, an optional way is to introduce a guard interval and insert a period without data transmission between the two scheduling times for the uplink and the two scheduling times for the downlink to avoid potential conflicts.

[0055] In a specific embodiment of the present invention, assume that the current time is t = 5 seconds and the round-trip delay is K = 100 milliseconds. The base station assigns a downlink task to a certain user equipment, and the scheduling time is t. At the same time, it plans to assign an uplink task, which can be the scheduling of uplink services or the periodic scheduling of common channels. The system determines that the time when the base station receives the uplink is T_uplink_receive, and assume this time is 5.1 seconds. To verify whether there is a conflict, the system adds the round-trip delay to the time when the base station schedules the downlink, that is, 5 seconds + 100 milliseconds = 5.1 seconds. Then, the system compares t + K = 5 seconds + 100 milliseconds = 5.1 seconds with the time T_uplink_receive = 5.1 seconds when the base station receives the uplink. Since the two are equal, the system determines that there is a potential conflict, so the downlink scheduling is not performed at this time slot. On the contrary, if the verification result shows no conflict, the system will schedule the downlink at the target time. For the uplink scheduling task planned by the base station, according to the protocol requirements, the UE must send the uplink scheduling after receiving the downlink UCI, so there is no need to judge the conflict with the service scheduling. However, it is still necessary to judge whether there is an uplink-downlink conflict with the periodic signal of the common channel. For the uplink target time T_uplink_receive, assume that there is a periodic signal of a downlink common channel with a period of T d , and at time t within this period cd the common signal for downlink scheduling is performed, then it is necessary to judge whether (T_uplink_receive - K) % T d and t cd have a potential conflict, where % represents the modulo operation. If the verification result shows a conflict, the system does not perform the uplink scheduling at this time. If there is no conflict, the system will schedule the uplink at the target time.

[0056] Based on this, by accurately calculating and verifying the first link scheduling time and the second link scheduling time on the user equipment side, the system can effectively avoid conflicts between the uplink and downlink. This precise time management mechanism enables the system to ensure that the task scheduling of different user equipments does not interfere with each other in a complex satellite communication environment, further improving the resource utilization rate and the overall performance of the network. The system can accurately coordinate the time arrangement of the uplink and downlink, improving the reliability and efficiency of communication. In addition, through the careful verification of the target time, the system enhances the adaptability and robustness of the scheduling strategy, ensuring high-quality communication even in a highly dynamic satellite communication environment.

[0057] Further, the time allocation information of the uplink is a scheduling status index table; obtaining the time allocation information of the uplink includes: initializing the scheduling status index table based on the target time; setting identification bits in the scheduling status index table based on the predicted uplink arrival time, where the scheduling status index table is used to indicate that there is an uplink scheduling task at the time corresponding to the identification bit.

[0058] Among them, the scheduling status index table is a data structure used to record whether there is an uplink scheduling task at a specific time, usually implemented in the form of a bitmap. When the identification bit is "1", it indicates that there is an uplink scheduling task at the corresponding time, while when the identification bit is "0", it indicates that there is no scheduling task at the corresponding time. The target time refers to the specific time point when the system plans to perform scheduling, and the predicted uplink arrival time is the time when the uplink data arrives at the base station calculated based on the delay information and the task requirements of the user equipment.

[0059] In practical applications, the system first initializes the scheduling status index table based on the target time. The scheduling status index table is an array of bitmaps, and its length corresponds to the time units (such as symbols, time slots, or sub-frames) within the target time range. In the initial state, all bits are set to "0", indicating that no scheduling tasks have been allocated yet. Then, for the planned uplink scheduling, the system sets the corresponding identification bit to "1" in the scheduling status index table according to the expected uplink arrival time.

[0060] In a specific embodiment of the present invention, assume that the current target time is n, and the system initializes a scheduling status index table with a length of 11, and the initial values are all "0". Subsequently, after completing an uplink scheduling with a target reception time of n + 11, the system sets the identification bits one by one according to the RTT of the possible positions of multiple user equipments. For example, the RTT of a certain UE position is 7.5. Since 11 - 7.5 = 3.5, the system sets the 3rd and 4th bits in the scheduling status index table to "1". Finally, the scheduling status index table may be [0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 0], indicating that there may be a conflict in the scheduling task of the uplink between n + 3 and n + 4 on the UE side. This bitmap-form index table is not only convenient for quick query but also can efficiently support subsequent conflict verification and resource allocation operations.

[0061] Based on this, by using the scheduling status index table to record the uplink scheduling tasks, the system can manage time resources intuitively and efficiently. This mechanism not only reduces the computational complexity in the resource allocation process but also ensures the accuracy and consistency of the scheduling tasks. The system can quickly identify which times have been occupied, thereby avoiding potential conflicts between the uplink and downlink, and further improving the flexibility of scheduling and the overall performance of the network.

[0062] Step 306: If not, schedule the uplink and downlink at the target time, where the time allocation information is used to represent the time when the user equipment performs the scheduling task.

[0063] Among them, if the verification result shows that there is no conflict between the first link scheduling time and the second link scheduling time, the downlink scheduling is performed at the target time; if there is a conflict, no scheduling is performed.

[0064] In practical applications, the system first judges whether the scheduling conditions are met based on the previous verification results. The previous verification results include the above-mentioned service scheduling verification results and the periodic scheduling verification results of the common channels planned to be executed. If there is no conflict between the first link scheduling time and the second link scheduling time, the system will determine the specific scheduling task at the target time according to the time allocation information. For example, if the task at the target time is downlink scheduling, the system will prepare to send downlink data to the user equipment according to the predetermined time allocation information; if the task is uplink scheduling, the system will notify the user equipment to send uplink data at the target time. During this process, the system needs to ensure that all relevant time-frequency resources have been correctly allocated and the user equipment is ready to receive or send data.

[0065] In a specific embodiment of the present invention, it is assumed that the system plans to schedule a downlink task for a certain user equipment at a certain moment. The time when the scheduling DCI is sent is T0, the target time is T1, and the HARQ (Hybrid Automatic Repeat reQuest) feedback time is T2. After the system confirms through the previous verification steps that there is no conflict between the first link scheduling time and the second link scheduling time corresponding to the downlink scheduling of T0 and T1, and there is no conflict between the first link scheduling time and the second link scheduling time corresponding to the uplink scheduling of T2, the system starts to execute the scheduling task. According to the time allocation information, the system sends the downlink DCI scheduling to the UE through the PDCCH at the T0 moment, sends the downlink data to the UE through the Physical Downlink Shared Channel (PDSCH) at the T1 moment, and prepares to receive the PUCCH (Physical Uplink Control Channel) resources of the uplink HARQ at the T2 moment. At the same time, the system ensures that all necessary resource preparations and mode switching operations have been completed within the protection interval time before this. If the verification result shows that there is a conflict, the system will not perform the scheduling task at the target time, but re-plan the scheduling time to ensure the smooth progress of subsequent tasks.

[0066] Further, the round-trip delay information includes a first delay of the user equipment at the sub-satellite point closest to the satellite and a second delay of the user equipment at the sub-satellite point farthest from the satellite; based on the time allocation information of the uplink and the round-trip delay information, verifying whether there is a conflict between the time when the user equipment receives the downlink at the target moment and the time when the user equipment initiates the uplink includes: in the scheduling status index table, determining a first verification interval based on the target moment, the first delay, and the second delay, where the first verification interval represents the potential conflict interval between the time when the user equipment receives the downlink and the time when the user equipment initiates the uplink; checking whether there is a flag bit within the verification interval; correspondingly, if not, scheduling the downlink at the target moment, including: if there is no flag bit within the first verification interval, scheduling the downlink at the target moment.

[0067] Among them, the round-trip delay information includes a first delay (minimum delay) of the user equipment at the sub-satellite point closest to the satellite and a second delay (maximum delay) of the user equipment at the sub-satellite point farthest from the satellite. The scheduling status index table is a bitmap structure used to record whether there is an uplink scheduling task at a specific moment, and a flag bit of "1" indicates that there is an uplink scheduling task at the corresponding moment. The first verification interval refers to a time interval determined based on the target moment, the first delay, and the second delay, and this interval represents the potential conflict interval between the time when the user equipment receives the downlink and the time when the user equipment initiates the uplink.

[0068] In practical applications, the system first obtains the time allocation information and the round-trip delay information on the base station side. Assume that the current target moment is n, and the round-trip delay information includes a first delay (minimum delay) and a second delay (maximum delay). The system calculates the first verification interval based on this information to check whether there is a conflict between the time when the user equipment receives the downlink at the target moment and the time when the user equipment initiates the uplink. Specifically, the system adds the first delay and the second delay to the target moment n to obtain a preliminary time range, and extends this time range to the entire round-trip delay to form the first verification interval. For example, if the first delay is K1 and the second delay is K2, the first verification interval can be expressed as [n + K1, n + K2]. Then, the system checks whether there is a position with a flag bit of "1" within the first verification interval in the scheduling status index table. If there is no position with a flag bit of "1" within the verification interval, it is considered that there is no conflict; if there is a flag bit of "1", there is a potential conflict and the scheduling strategy needs to be readjusted. For the verification method in the above steps, an optional method is to check each time slot within the verification interval one by one; another optional implementation method is to batch-check multiple time slots to improve efficiency.

[0069] In a specific embodiment of the present invention, assume that the current target time is n = 5 seconds, the first time delay K1 = 40 milliseconds, and the second time delay K2 = 80 milliseconds. The system initializes a scheduling status index table, and the initial values are all "0". The scheduling status index table is a bitmap structure, and a flag bit of "1" indicates that there is an uplink scheduling task at the corresponding time, which is filled by the uplink scheduling. The system first calculates the first verification interval, that is, [5 seconds + 40 milliseconds, 5 seconds + 80 milliseconds], and converts it into specific time slots. Assuming that each time slot is 1 millisecond, the verification interval is [slot40, slot80]. The system checks whether there is a position with a flag bit of "1" between slot40 and slot80 in the scheduling status index table. If the flag bits of all these time slots are "0", the system determines that there is no conflict and schedules the downlink at the target time n. Assume that the scheduling status index table shows that there is a flag bit of "1" at slot41, indicating that this time slot is occupied. The system will further evaluate whether it is necessary to adjust the scheduling strategy or insert a guard interval to avoid conflicts. If the verification result shows no conflict, the system will schedule the downlink at the target time.

[0070] Based on this, by accurately calculating the first verification interval and checking the flag bits in the scheduling status index table, the system can effectively avoid conflicts between the uplink and downlink. This mechanism not only ensures that the task scheduling of different user devices does not interfere with each other, but also improves the resource utilization rate and the overall performance of the network. The system can accurately coordinate the time arrangement of the uplink and downlink, improving the reliability and efficiency of communication.

[0071] Further, after scheduling the downlink, it further includes: obtaining the scheduling information of the uplink corresponding to the downlink; setting the flag bit in the scheduling status index table.

[0072] Among them, the uplink scheduling information refers to the channel resources used for control information or data transmission in the uplink that is synchronously planned when the base station allocates resources for the downlink. These channels include PUCCH and PUSCH (Physical Uplink Shared Channel), which are used for HARQ feedback and uplink data transmission respectively. k1, k2, and koffset are time offset parameters specified according to the 3GPP protocol, which are used to determine the specific scheduling time of the uplink.

[0073] In practical applications, the system first obtains the uplink scheduling information corresponding to the downlink. For example, after scheduling downlink n, according to the provisions of the 3GPP protocol, the system calculates that PUCCH may be scheduled for HARQ feedback at (n + k1 + koffset), and PUSCH may be scheduled for uplink data transmission at (n + k2 + koffset). Then, the system checks whether there is a periodic scheduling of the downlink common channel at (n + k1 + koffset - K) and (n + k2 + koffset - K), where K is the round-trip transmission delay, and the checking method is as described before. If the check result has no conflict, the system sets the corresponding flag bit in the scheduling status index table. Specifically, the system sets the (k1 + koffset)-th and (k2 + koffset)-th positions in the bitmap to "1" as needed to indicate that there are uplink scheduling tasks at these times. For the setting method in the above steps, one optional method is to calculate each time offset one by one and set the bit individually; another optional implementation method is to batch process multiple time offsets and update multiple flag bits in the scheduling status index table at one time, so as to improve efficiency. In addition, after scheduling is completed, the system moves the bitmap forward by one bit and checks whether there is an uplink common channel scheduling task in slot n + 65. If there is, the flag bit is set at the corresponding position as needed.

[0074] In a specific embodiment of the present invention, assume that the currently scheduled downlink slot is n = 10, k1 = 4, k2 = 8, and koffset = 2. According to the 3GPP protocol, the system calculates that PUCCH may be scheduled for HARQ feedback at (n + k1 + koffset) = 10 + 4 + 2 = slot 16, and PUSCH may be scheduled for uplink data transmission at (n + k2 + koffset) = 10 + 8 + 2 = slot 20. The system initializes a scheduling status index table with all initial values being "0". Then, if there is no conflict in the periodic scheduling of the downlink common channel, the system sets the 16th and 20th bits in the bitmap to "1" to indicate that there are uplink scheduling tasks at these times. Subsequently, the system moves the bitmap forward by one bit and checks whether there is an uplink common channel scheduling task in n + 65 = slot 75. If the system detects that PUSCH needs to be scheduled in slot 75, it sets the 75th bit in the bitmap to "1". In this way, the system can accurately record all uplink scheduling tasks related to the downlink.

[0075] Based on this, by combining the common channel scheduling information and the scheduling status index table, the system can efficiently manage the resource allocation of the uplink and downlink. This mechanism not only ensures the timeliness and accuracy of HARQ feedback and uplink data transmission, but also avoids potential resource conflicts.

[0076] Further, the time allocation information is the scheduling information of the downlink common channel, the first link scheduling time is the time when the user equipment initiates the uplink, and the second link scheduling time is the time when the user equipment schedules the downlink common channel; based on the time allocation information and the round-trip delay information, verifying whether there is a conflict between the first link scheduling time of the user equipment and the second link scheduling time corresponding to the time allocation information includes: obtaining the scheduling information of the downlink common channel; based on the scheduling information of the downlink common channel and the round-trip delay information, verifying whether there is a conflict between the time when the user equipment initiates the uplink corresponding to the target time and the time when the user equipment schedules the downlink common channel; correspondingly, if not, scheduling the uplink and downlink at the target time, including: if not, scheduling the uplink at the target time.

[0077] Among them, the first link scheduling time is the time when the user equipment initiates the uplink, and the second link scheduling time is the time when the user equipment schedules the downlink common channel. Verifying whether there is a conflict between these two scheduling times is to ensure that there is no interference between the uplink and downlink on the user equipment side.

[0078] In practical applications, the system first obtains the scheduling information of the downlink common channel. These information are usually generated by the base station according to network requirements and the task requests of user equipment, and include specific scheduling times and corresponding channel resources. Assume that the current target time is slot n. The system calculates the time when the user equipment initiates the uplink and the time when the user equipment schedules the downlink common channel based on this time. Then, the system adjusts these times using the round-trip delay information to consider the impact of signal propagation delay. For example, if the scheduling time of the downlink common channel is n, considering the round-trip delay K1 (minimum delay) and K2 (maximum delay), the time when the user equipment initiates the uplink can be expressed as [n - K2, n - K1]. The system checks each time within this interval to ensure that they do not conflict with the scheduling time of the downlink common channel. Specifically, the system maps the scheduling time of the downlink common channel to the corresponding position in the scheduling status index table and checks one by one whether there is a position with the flag bit "1" within this interval. If there is no conflict, the uplink and downlink can be scheduled at the target time; if there is a conflict, the scheduling strategy needs to be readjusted or a guard interval needs to be inserted to avoid conflicts.

[0079] In a specific embodiment of the present invention, assume that the current target time is n = 0 seconds, the scheduling time of the uplink is n = 60 milliseconds, the first delay K1 in the round-trip delay information is 40 milliseconds, and the second delay K2 is 80 milliseconds. The system first calculates the time range when the user equipment initiates the uplink, that is, [60 - 80ms, 60 - 40ms]. Assuming that each time slot is 1 millisecond, this range is converted to [-20, 20]. Since the time slot number cannot be negative, the system adjusts it to [0, 20]. Then, the system checks whether there is a position with the identification bit "1" between slot0 and slot20 in the scheduling status index table. If the identification bits of all these time slots are "0", the system determines that there is no conflict and schedules the uplink at the target time n. Assume that the scheduling status index table shows that there is an identification bit "1" at 1, indicating that this time slot has been occupied. The system will further evaluate whether it is necessary to adjust the scheduling strategy or insert a guard interval to avoid conflicts. If the verification result shows no conflict, the system will schedule the uplink at the target time and notify the user equipment to initiate the uplink at an appropriate time.

[0080] Based on this, by accurately calculating and verifying the time when the user equipment initiates the uplink and the time when the user equipment schedules the downlink common channel, the system can effectively avoid conflicts between the uplink and the downlink.

[0081] Further, the round-trip delay information includes the first delay of the user equipment near the sub-satellite point and the second delay of the user equipment far from the sub-satellite point; based on the common channel scheduling information of the downlink and the round-trip delay information, verifying whether there is a conflict between the time when the user equipment initiates the uplink corresponding to the target time and the time when the user equipment schedules the downlink common channel includes: obtaining the time slot offset parameter, and determining the actual uplink scheduling time based on the timing offset parameter and the target time; in the scheduling status index table, determining the second verification interval based on the actual scheduling time, the first delay and the second delay, where the second verification interval represents the potential conflict interval between the time when the user equipment initiates the uplink and the time when the user equipment schedules the downlink common channel; checking whether there is an identification bit indicating an existing downlink common channel scheduling in the verification interval; correspondingly, if not, scheduling the uplink at the target time, including; if there is no identification bit in the second verification interval, scheduling the uplink at the target time.

[0082] Among them, the scheduling status index table is a bitmap structure, and the identification bit "1" indicates that there is a scheduling task for the downlink common channel at the corresponding time. The time slot offset parameter is used to calculate the actual uplink scheduling time according to the time offset specified by the 3GPP protocol. The second verification interval refers to a time interval determined based on the actual scheduling time, the first delay and the second delay, and this interval represents the potential conflict interval between the time when the user equipment initiates the uplink and the time when the user equipment schedules the downlink common channel.

[0083] In practical applications, the system first obtains the common channel scheduling information and round-trip delay information of the downlink. Assume that the current target time is n, and the first delay K1 and the second delay K2 are known. The system obtains the time slot offset parameter koffset, and determines the actual scheduling time of the uplink based on this parameter and the target time n. Specifically, the system calculates the actual scheduling time of the uplink as (n + koffset). Then, the system adjusts this actual scheduling time using the first delay K1 and the second delay K2 to form a potential conflict interval (i.e., the second verification interval) to consider the impact of signal propagation delay. For example, the second verification interval can be expressed as [(n + koffset - K2), (n + koffset - K1)]. The system checks whether there are positions with the identification bit "1" in this interval in the scheduling status index table, and these identification bits represent the scheduling tasks of the existing downlink common channels. If there is no conflict, the uplink and downlink can be scheduled at the target time; if there is a conflict, the scheduling strategy needs to be readjusted or a guard interval needs to be inserted to avoid the conflict.

[0084] In a specific embodiment of the present invention, assume that the current target time is n = 60 milliseconds, the first delay K1 = 40 milliseconds, the second delay K2 = 80 milliseconds, and the time slot offset parameter koffset = 50. The system initializes a scheduling status index table with all initial values being "0". The system first calculates the actual scheduling time of the uplink as (60 + 50) = 110. Then, the system calculates the second verification interval according to the first delay and the second delay, that is, [110 - 80ms, 110 - 40ms]. Assuming that each time slot is 1 millisecond, this range is converted to [30, 70]. The system checks whether there are positions with the identification bit "1" between 30 and 70 in the scheduling status index table. If the identification bits of all these time slots are "0", the system determines that there is no conflict and schedules the uplink at the target time n. Assume that the scheduling status index table shows that there is an identification bit "1" at 45, indicating that this time slot is occupied. The system will further evaluate whether it is necessary to adjust the scheduling strategy or insert a guard interval to avoid the conflict. If the verification result shows no conflict, the system will schedule the uplink at the target time and notify the user equipment to initiate the uplink at an appropriate time.

[0085] Based on this, by accurately calculating and verifying the time when the user equipment initiates the uplink and the time when the user equipment schedules the downlink common channel, the system can effectively avoid conflicts between the uplink and the downlink.

[0086] Furthermore, the uplink and downlink scheduling method further includes: updating the service area information of the satellite at preset intervals; updating the round-trip delay information based on the updated service area information of the satellite.

[0087] Among them, the preset period refers to the time interval at which the system regularly updates the service area information and the round-trip delay information. The calculation basis is to ensure that the change value of RTT caused by satellite movement or service area change within this period is less than 1 slot, so as to avoid scheduling conflicts.

[0088] In practical applications, the system first determines a reasonable preset period T according to the orbital parameters of the satellite and the dynamic characteristics of the service area. The calculation of this period T is based on factors such as the movement speed of the satellite, the orbital altitude, and the earth's rotation, ensuring that within the time T, the change in the satellite's position will not cause the RTT to change by more than the time length of 1 slot. For example, if the duration of each slot is 1 millisecond, it is necessary to ensure that the change value of RTT within the time T is less than 1 millisecond. Then, the system re-obtains the latest service area information of the satellite every preset period T, including the current position of the satellite, the longitude and latitude of the center point of the service area, and the size parameters of the service area. Based on this updated information, the system recalculates the round-trip delay information between the satellite and the user equipment. Specifically, the system re-derives the first delay (minimum delay) of the user equipment near the sub-satellite point and the second delay (maximum delay) of the far sub-satellite point according to the updated satellite position and service area information. Subsequently, the system applies the updated round-trip delay information to the subsequent uplink and downlink scheduling tasks to ensure the accuracy and reliability of the scheduling strategy.

[0089] In a specific embodiment of the present invention, it is assumed that a certain low-earth orbit satellite currently covers a circular service area with a radius of 1000 kilometers, and the satellite is located 350 kilometers above the center of the service area. The system sets the preset period T to 1 second and ensures that the change value of RTT caused by satellite movement within 1 second is less than 1 slot (assuming each slot is 1 millisecond). Every 1 second, the system re-obtains the latest position information of the satellite and the service area parameters. For example, at a certain moment, the position of the satellite changes slightly, and the longitude and latitude of the center point of the service area also shift. The system recalculates the first delay of the user equipment near the sub-satellite point and the second delay of the far sub-satellite point according to this updated information. Assuming that the first delay changes from the original 40 milliseconds to 42 milliseconds, and the second delay changes from 80 milliseconds to 83 milliseconds, the system records these updated delay information and applies it to the subsequent scheduling tasks. In this way, the system can timely reflect the changes of the satellite and the service area, ensuring the accuracy of the scheduling strategy.

[0090] Based on this, by regularly updating the service area information and the round-trip delay information of the satellite, the system can dynamically adapt to the impacts brought by satellite movement and service area changes.

[0091] Applied to the uplink and downlink scheduling method, by obtaining the service area information of the satellite, calculating the round-trip delay information between the satellite and the user equipment, and performing verification based on the time allocation information, scheduling conflicts on the uplink and downlink of the user equipment are avoided, ensuring that there will be no conflict with the existing resource allocation of the user equipment when scheduling the uplink and downlink at the target moment, thereby effectively improving the time-frequency resource utilization rate. Resource waste is reduced, the coordination of the uplink and downlink is optimized, and the overall network efficiency is improved.

[0092] The following combines the attached Figure 4 , taking the application of the uplink and downlink scheduling method provided by the present invention in HD-FDD under the non-terrestrial network NTN as an example, the uplink and downlink scheduling method will be further described. Among them, Figure 4 is a flowchart of the processing procedure of an uplink and downlink scheduling method provided by an embodiment of the present invention, specifically including the following steps.

[0093] Step 402: Calculate the transmission delay range within the wave position covered by each satellite.

[0094] Specifically, referring to Figure 5 shown, Figure 5 is a schematic diagram of another round-trip delay calculation method provided by an embodiment of the present invention. Among them, O is the center of the earth, S is the satellite, C is the center point of the wave position, the large circle in the figure is the cross-section of the plane SOC on the earth, D and E are the edge points of the wave position, A is the intersection point of SO on the earth's surface, denote ∠SOC as θ, the length of SO is h, the distance of SC is s, and the radius of the earth is r = 6371 (km). Then in △SOC:

[0095] Among them, s can be calculated according to the satellite position and the longitude and latitude of the beam center point, h is obtained according to the satellite position, and the minimum and maximum delays respectively correspond to Figure 5 the D and E points in, denote ∠SOD as θ1, ∠SOE as θ2, then the distances of SD and SE can be expressed as the following formula (1): Formula (1) θ1 and θ2 can be expressed as the following formula (2): Formula (2) Alternatively, the range of s can be calculated using the inequality (3) i to save the computing resources of the processor: Formula (3) Both formula (1) and formula (3) are used to calculate the possible distance from the UE to the satellite, and one of them is actually used. Where d is the wave position radius, that is, the length of arc CD or CE. From this, the RTT range can be calculated through formula (4): Formula (4) Convert the RTT range to the scheduled time slot (slot) value, and extend one slot forward and backward respectively to form an interval (K1, K2). This is to cope with the dynamic fluctuation of RTT caused by the high-speed movement of the satellite or the change of the user equipment position in the satellite communication system. By extending the time slot range, it can be ensured that when the RTT changes due to the relative movement between the satellite and the user equipment, the uplink and downlink scheduling conflicts can still be effectively avoided. This design not only improves the robustness of the scheduling, but also ensures the stability and reliability of the communication link, while reducing the resource waste or performance degradation caused by the RTT prediction error.

[0096] Step 404: Denote the current slot as n and perform downlink scheduling judgment.

[0097] Specifically, configure a bitmap for the initial scheduled half-duplex user equipment (HD-UE). Its length is determined by the maximum delay within the satellite coverage area, for example, set to 64. This bitmap is based on the current uplink time slot (slot) and is used to identify whether there is an uplink scheduling in the next 64 slots. In the initial state, all bit positions are set to 0, indicating that no uplink scheduling has been performed yet. The purpose of this step is to create an efficient scheduling status index table for dynamically tracking the future uplink usage and avoiding resource conflicts.

[0098] When scheduling the UE downlink, the gNB first checks whether there is an uplink scheduling in the next 64 slots based on the current uplink slot. If there is an uplink scheduling in a certain slot, set the corresponding bit position to 1, and keep other bit positions unchanged. This operation ensures that the bitmap can accurately reflect the resource occupancy of the future uplink and provides a reliable basis for subsequent downlink scheduling, avoiding conflicts caused by the time overlap of the uplink and downlink.

[0099] Since the signal transmission of the current downlink time slot n to the user equipment requires a time delay of RTT, and the range of RTT converted to slot values is (K1, K2), the actually affected uplink time slot is n + K. Essentially, this is to check whether there is a conflict between n + K / 2 (the time point when the signal reaches the user equipment) and -K / 2 (the time point when the user equipment initiates the uplink signal) represented by 1 in the bitmap. In other words, it checks whether n + K overlaps with the time point represented by 1 in the bitmap, that is, checks whether there is a bit set to 1 in the range from n + K1 to n + K2. If there is a conflict, wait for the next available time slot; otherwise, continue with the subsequent check. The scheduling time slot of the downlink PDSCH is (n + k0), and after RTT, the affected uplink time slot is n + k0 + K. Therefore, it is also necessary to check whether there is a bit set to 1 in the range from n + k0 + K1 to n + k0 + K2 in the bitmap. If there is a conflict, wait for the next available time slot; otherwise, continue with the subsequent check. This verification mechanism effectively avoids the uplink and downlink link conflicts caused by satellite movement or RTT fluctuations.

[0100] After completing the scheduling check of the downlink time slot n, PUCCH will be scheduled on n + k1 + koffset for HARQ feedback. This uplink scheduling affects the downlink time slot of n + k1 + koffset - K. Therefore, it is necessary to check the scheduling status of the downlink common channel within the range of (n + k1 + koffset - K2, n + k1 + koffset - K1). Essentially, this is to check whether there is a conflict between n + k1 + koffset - K / 2 (the time when the uplink signal reaches the satellite) and the downlink common channel scheduling time + K / 2 (the time when the downlink signal reaches the user equipment), that is, to check whether n + k1 + koffset - K overlaps with the downlink common channel scheduling time. If there is a conflict, wait for the next available scheduling slot; otherwise, continue with the current scheduling. After completing the scheduling, it is necessary to set the bit at k1 + koffset in the bitmap to "1". This step ensures that the bitmap can accurately record the scheduling status of possible future HARQ feedback and avoids conflicts between these key operations and other downlink scheduling. k1, k2, and koffsed are all time slot parameters specified by the 3GPP protocol to ensure that the scheduling complies with the standard specifications.

[0101] After each scheduling is completed, the bitmap is slid forward by one bit, and it is checked whether there is an uplink common channel scheduling requirement for the slot of n + 65. If so, the corresponding bit is set to "1"; otherwise, it remains "0". In this way, the bitmap always maintains the scheduling status tracking of the next 64 slots, ensuring the real-time and accuracy of the scheduling decision. This step realizes the dynamic update of the bitmap and ensures that it can continuously support subsequent scheduling operations.

[0102] The above steps of downlink verification - scheduling are executed cyclically, continuously verifying the conflicts between the downlink and uplink, updating the bitmap status, and completing the scheduling operation. This cyclic process constitutes the complete scheduling logic, ensuring that the system can efficiently allocate resources in a dynamically changing satellite communication environment, avoiding conflicts between the uplink and downlink, and improving the overall network performance and user experience.

[0103] Step 406: Denote the current slot as n and perform uplink scheduling judgment.

[0104] Specifically, assume that an uplink service is scheduled at n. The UCI signal of the current downlink slot n needs a time delay of RTT to be transmitted to the user equipment. After converting RTT into slot values, the range is (K1, K2). Therefore, the actually affected uplink slot is n + K. Essentially, this is to verify whether there is a conflict between n + K / 2 (the time point when the signal reaches the user equipment) and -K / 2 of the moment represented by 1 in the bitmap (the time point when the user equipment initiates an uplink signal). In other words, verify whether n + K overlaps with the moment represented by 1 in the bitmap, that is, check whether there is a bit set to 1 in the range from n + K1 to n + K2. The uplink service PUSCH will be actually transmitted at n + k2 + koffset. Due to the existence of RTT in satellite communication, the corresponding downlink signal will coincide with the uplink signal at the time point of n + k2 + koffset - K. Therefore, it is necessary to check the scheduling status of the downlink common channel within the range of (n + k2 + koffset - k2, n + k2 + koffset - k1). Essentially, this is to verify whether there is a conflict between n + k2 + koffset - K / 2 (the time when the uplink signal reaches the satellite) and the downlink common channel scheduling moment +K / 2 + (the time when the downlink signal reaches the user equipment), that is, verify whether n + k2 + koffset - K overlaps with the downlink common channel scheduling moment. If there is a conflict, wait for the next available scheduling slot; otherwise, continue with the current scheduling and set the (k2 + koffset)-th position in the bitmap in step 404 to "1". This step ensures that the bitmap can accurately record the scheduling status of future possible uplink services, avoiding conflicts between these key operations and other downlink schedules. This verification mechanism ensures that the uplink scheduling does not interfere with the planned downlink common channel resources.

[0105] According to the 3GPP protocol, koffset > K, so n + k2 + koffset - K > n. This indicates that the actual transmission time of the uplink service is always later than the current scheduling moment n, thus avoiding a direct time overlap with the scheduled downlink service. Therefore, in this case, there is no need to consider the impact of the scheduled downlink service on the uplink scheduling, and only the conflicts that may be brought about by the downlink common channel scheduling need to be concerned about. This design simplifies the scheduling logic while ensuring the coordination of the uplink and downlink links and the efficiency of resource allocation.

[0106] Step 408: Periodically perform RTT update calculation.

[0107] Specifically, due to the movement of the satellite, the RTT will change over time. Therefore, it is necessary to periodically calculate the RTT to ensure the accuracy of scheduling. The standard for setting the calculation period T is that within this period, the change in the RTT will not cause the corresponding slot value to change by more than 1 slot. This can ensure that the fluctuation of the RTT within each period will not affect the precise scheduling of the uplink and downlink links, thus avoiding resource conflicts or scheduling failures caused by inaccurate RTT estimation and ensuring the stability and reliability of the communication system. This periodic update mechanism can dynamically adapt to the impact brought by satellite movement and maintain the optimal state of network performance.

[0108] Corresponding to the above method embodiments, the present invention also provides embodiments of an uplink and downlink link scheduling device. Figure 6 It is a schematic structural diagram of an uplink and downlink link scheduling device provided by an embodiment of the present invention. As Figure 6 shown, the device includes: A calculation module 602, configured to calculate the round-trip delay information between the satellite and the user equipment based on the service area information of the satellite; A verification module 604, configured to verify whether there is a conflict between the first link scheduling moment of the user equipment and the second link scheduling moment corresponding to the time allocation information based on the time allocation information and the round-trip delay information; A scheduling module 606, configured to, if not, schedule the uplink and downlink links at the target moment, where the time allocation information is used to represent the moment when the user equipment performs the scheduling task.

[0109] Optionally, the calculation module 602 is further configured to obtain the satellite position information, the longitude and latitude information of the center of the service area, and the size parameters of the service area; determine the angular offset of the user equipment based on the satellite position information, the longitude and latitude information, and the size parameters, where the angular offset is the included angle between the position offset of the user equipment relative to the projection of the center of the service area on the earth's surface and the center of the earth; calculate the transmission distance based on the angular offset and the satellite position information, and calculate the round-trip delay information between the satellite and the user equipment based on the transmission distance.

[0110] Optionally, the time allocation information is the time allocation information for the uplink, the first link scheduling time is the time when the user equipment receives the downlink, and the second link scheduling time is the time when the user equipment initiates the uplink; correspondingly, the verification module 604 is further configured to obtain the time allocation information for the uplink; based on the time allocation information for the uplink and the round-trip delay information, verify whether there is a conflict between the time when the user equipment receives the downlink corresponding to the target time and the time when the user equipment initiates the uplink; correspondingly, the scheduling module 606 is further configured to, if not, schedule the downlink at the target time.

[0111] Optionally, the time allocation information for the line link is the scheduling status index table; correspondingly, the verification module 604 is further configured to initialize the scheduling status index table based on the target time; set a flag bit in the scheduling status index table based on the predicted uplink arrival time, where the scheduling status index table is used to indicate that there is an uplink scheduling task at the time corresponding to the flag bit.

[0112] Optionally, the round-trip delay information includes a first delay of the user equipment near the sub-satellite point and a second delay of the far sub-satellite point; correspondingly, the verification module 604 is further configured to determine a first verification interval in the scheduling status index table based on the target time, the first delay, and the second delay, where the first verification interval represents the potential conflict interval between the time when the user equipment receives the downlink and the time when the user equipment initiates the uplink; check whether there is a flag bit in the verification interval; correspondingly, the scheduling module 606 is further configured to, if there is no flag bit in the first verification interval, schedule the downlink at the target time.

[0113] Optionally, the verification module 604 is further configured to obtain the common channel scheduling information for the uplink corresponding to the downlink; set a flag bit in the scheduling status index table based on the common channel scheduling information.

[0114] Optionally, the time allocation information is the common channel scheduling information for the downlink, the first link scheduling time is the time when the user equipment initiates the uplink, and the second link scheduling time is the time when the user equipment schedules the downlink common channel; correspondingly, the verification module 604 is further configured to obtain the common channel scheduling information for the downlink; based on the common channel scheduling information for the downlink and the round-trip delay information, verify whether there is a conflict between the time when the user equipment initiates the uplink corresponding to the target time and the time when the user equipment schedules the downlink common channel; correspondingly, the scheduling module 606 is further configured to, if not, schedule the uplink at the target time.

[0115] Optionally, the round-trip delay information includes a first delay of the user equipment at the sub-satellite point and a second delay of the user equipment at the far sub-satellite point; correspondingly, the verification module 604 is further configured to obtain a time slot offset parameter, determine the actual uplink scheduling time based on the timing offset parameter and the target time; in the scheduling status index table, determine a second verification interval based on the actual scheduling time, the first delay and the second delay, where the second verification interval represents a potential conflict interval between the time when the user equipment initiates an uplink and the time when the user equipment schedules a downlink common channel; check whether there is a flag bit indicating an existing downlink common channel scheduling in the verification interval; correspondingly, the scheduling module 606 is further configured to, if there is no flag bit in the second verification interval, schedule the uplink at the target time.

[0116] Optionally, the uplink and downlink scheduling device further includes a delay update module, configured to update the service area information of the satellite every preset period; update the round-trip delay information based on the updated service area information of the satellite.

[0117] Applied to the uplink and downlink scheduling device, first, the calculation module 602 calculates the round-trip delay information between the satellite and the user equipment based on the service area information of the satellite to ensure an accurate understanding of the actual propagation delay of different user equipment. Then, the verification module 604 uses this round-trip delay information and time allocation information to verify whether there is a conflict between the first link scheduling time and the second link scheduling time of the user equipment, thereby avoiding potential interference between the uplink and downlink. If the verification result shows no conflict, the scheduling module 606 schedules the uplink and downlink at the target time to ensure that the scheduling performed at this time does not conflict with the existing resource allocation of the user equipment. It effectively improves the time-frequency resource utilization rate, reduces resource waste, optimizes the coordination of the uplink and downlink, and improves the overall network efficiency.

[0118] The above is a schematic solution of an uplink and downlink scheduling device according to an embodiment of the present invention. It should be noted that the technical solution of the uplink and downlink scheduling device and the technical solution of the above uplink and downlink scheduling method belong to the same concept. For the details not described in detail in the technical solution of the uplink and downlink scheduling device, reference can be made to the description of the technical solution of the above uplink and downlink scheduling method.

[0119] Figure 7 FIG. shows a structural block diagram of a computing device 700 according to an embodiment of the present invention. The components of the computing device 700 include, but are not limited to, a memory 710 and a processor 720. The processor 720 is connected to the memory 710 through a bus 730, and a database 750 is used to store data.

[0120] The computing device 700 also includes an access device 740, which enables the computing device 700 to communicate via one or more networks 760. Examples of such networks include the Public Switched Telephone Network (PSTN), Local Area Network (LAN), Wide Area Network (WAN), Personal Area Network (PAN), or a combination of communication networks such as the Internet. The access device 740 may include one or more of any type of wired or wireless network interfaces (e.g., network interface controller (NIC)), such as an IEEE 802.11 Wireless Local Area Network (WLAN) wireless interface, Worldwide Interoperability for Microwave Access (Wi-MAX) interface, Ethernet interface, Universal Serial Bus (USB) interface, cellular network interface, Bluetooth interface, Near Field Communication (NFC).

[0121] In one embodiment of the present invention, the above components of the computing device 700, as well as Figure 7 other components not shown, may also be connected to each other, for example, via a bus. It should be understood that Figure 7 the block diagram of the computing device shown is for illustrative purposes only and is not a limitation on the scope of the present invention. Those skilled in the art can add or replace other components as needed.

[0122] The computing device 700 can be any type of stationary or mobile computing device, including mobile computers or mobile computing devices (e.g., tablet computers, personal digital assistants, laptop computers, notebook computers, netbooks, etc.), mobile phones (e.g., smartphones), wearable computing devices (e.g., smartwatches, smart glasses, etc.) or other types of mobile devices, or stationary computing devices such as desktop computers or personal computers (PCs). The computing device 700 can also be a mobile or stationary server.

[0123] Wherein, the processor 720 is used to execute the following computer program / instructions, and when the computer program / instructions are executed by the processor, the steps of the above uplink and downlink scheduling method are implemented.

[0124] Each embodiment in the present invention is described in a progressive manner. For the same or similar parts among the embodiments, reference can be made to each other. Each embodiment focuses on the differences from other embodiments. In particular, for the embodiment of the computing device, since it is basically similar to the embodiment of the uplink and downlink scheduling method, the description is relatively simple, and the relevant parts can refer to the partial description of the embodiment of the uplink and downlink scheduling method.

[0125] An embodiment of the present invention further provides a computer-readable storage medium, which stores computer programs / instructions. When the computer programs / instructions are executed by a processor, the steps of the above-mentioned uplink and downlink scheduling method are implemented.

[0126] Each embodiment in the present invention is described in a progressive manner. For the same or similar parts among the embodiments, reference can be made to each other. Each embodiment focuses on the differences from other embodiments. In particular, for the embodiment of the computer-readable storage medium, since it is basically similar to the embodiment of the uplink and downlink scheduling method, the description is relatively simple, and the relevant parts can refer to the partial description of the embodiment of the uplink and downlink scheduling method.

[0127] An embodiment of the present invention further provides a computer program product, including computer programs / instructions. When the computer programs / instructions are executed by a processor, the steps of the above-mentioned uplink and downlink scheduling method are implemented.

[0128] The above is a schematic solution of a computer program product in this embodiment. It should be noted that the technical solution of this computer program product and the technical solution of the above-mentioned uplink and downlink scheduling method belong to the same concept. For the details not described in the technical solution of the computer program product, reference can be made to the description of the technical solution of the above-mentioned uplink and downlink scheduling method.

[0129] The specific embodiments of the present invention are described above. Other embodiments are within the scope of the appended claims. In some cases, the actions or steps recited in the claims can be performed in a different order than in the embodiments and still achieve the desired result. Additionally, the processes depicted in the figures do not necessarily require the particular order or sequential order shown to achieve the desired result. In certain embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0130] The computer instructions include computer program code, which may be in the form of source code, object code, executable files, or some intermediate forms, etc. The computer-readable medium may include: any entity or device capable of carrying the computer program code, recording media, USB flash drives, mobile hard disks, magnetic disks, optical disks, computer memories, read-only memories (ROMs), random access memories (RAMs), electrical carrier signals, telecommunication signals, and software distribution media, etc.

[0131] It should be noted that, for the foregoing method embodiments, for the sake of simplicity of description, they are all expressed as a series of action combinations. However, those skilled in the art should be aware that the embodiments of the present invention are not limited by the described action sequences, because according to the embodiments of the present invention, some steps may be performed in other sequences or simultaneously. Secondly, those skilled in the art should also be aware that the embodiments described in the specification are all preferred embodiments, and the actions and modules involved are not necessarily essential to the embodiments of the present invention.

[0132] In the above embodiments, the descriptions of the various embodiments have their own emphases. For the parts not detailed in a certain embodiment, reference may be made to the relevant descriptions of other embodiments.

[0133] The preferred embodiments of the present invention disclosed above are only used to help explain the present invention. The alternative embodiments do not describe all the details in detail, nor do they limit the invention to the specific embodiments described. Obviously, according to the content of the embodiments of the present invention, many modifications and variations can be made. The present invention selects and specifically describes these embodiments to better explain the principles and practical applications of the embodiments of the present invention, so that those skilled in the art can well understand and utilize the present invention. The present invention is only limited by the claims and their full scope and equivalents.

Claims

1. A method for uplink and downlink scheduling, characterized in that Applied to a base station, the base station is deployed on a satellite and includes: Calculating the round-trip delay information between the satellite and the user equipment based on the service area information of the satellite; Based on the time allocation information and the round-trip delay information, verifying whether there is a conflict between the first link scheduling time of the user equipment and the second link scheduling time corresponding to the time allocation information, where the first link scheduling time and the second link scheduling time are determined under the constraint of link scheduling at the target time; If not, then scheduling the uplink and downlink at the target time, where the time allocation information is used to represent the time when the user equipment performs the scheduling task.

2. The method according to claim 1, wherein The calculating the round-trip delay information between the satellite and the user equipment based on the service area information of the satellite includes: Obtaining the satellite position information, the longitude and latitude information of the center of the service area, and the size parameters of the service area; Based on the satellite position information, the longitude and latitude information, and the size parameters, determining the angular offset of the user equipment, where the angular offset is the angle between the position offset of the user equipment relative to the projection of the center of the service area on the earth's surface and the center of the earth; Based on the angular offset and the satellite position information, calculating the transmission distance, and based on the transmission distance, calculating the round-trip delay information between the satellite and the user equipment.

3. The method according to claim 1, characterized in that, The time allocation information is the time allocation information of the uplink, the first link scheduling time is the time when the user equipment receives the downlink, and the second link scheduling time is the time when the user equipment initiates the uplink; the verifying whether there is a conflict between the first link scheduling time of the user equipment and the second link scheduling time corresponding to the time allocation information based on the time allocation information and the round-trip delay information includes: Obtaining the time allocation information of the uplink; Based on the time allocation information of the uplink and the round-trip delay information, verifying whether there is a conflict between the time when the user equipment receives the downlink and the time when the user equipment initiates the uplink corresponding to the target time; Correspondingly, the if not, then scheduling the uplink and downlink at the target time includes: If not, then scheduling the downlink at the target time.

4. The method according to claim 3, characterized in that, The time allocation information of the uplink is a scheduling status index table; the obtaining the time allocation information of the uplink includes: Initializing the scheduling status index table based on the target time; Based on the predicted uplink arrival time, setting a flag bit in the scheduling status index table, where the scheduling status index table is used to indicate that there is a scheduling task for the uplink at the time corresponding to the flag bit.

5. The method according to claim 4, wherein The round-trip delay information includes the first delay of the user equipment near the sub-satellite point and the second delay of the user equipment far from the sub-satellite point; the verifying whether there is a conflict between the time when the user equipment receives the downlink and the time when the user equipment initiates the uplink corresponding to the target time based on the time allocation information of the uplink and the round-trip delay information includes: In the scheduling status index table, determine a first verification interval based on the target time, the first time delay, and the second time delay, where the first verification interval represents a potential conflict interval between the time when the user equipment receives the downlink and the time when the user equipment initiates the uplink; Check whether there is a flag bit within the verification interval; Correspondingly, if not, scheduling the downlink at the target time includes; If there is no flag bit within the first verification interval, schedule the downlink at the target time.

6. The method according to claim 5, wherein After scheduling the downlink, it further includes: Obtain the common channel scheduling information of the uplink corresponding to the downlink; Based on the common channel scheduling information, set a flag bit in the scheduling status index table.

7. The method according to claim 1, characterized in that, The time allocation information is the common channel scheduling information of the downlink, the first link scheduling time is the time when the user equipment initiates the uplink, and the second link scheduling time is the time when the user equipment schedules the downlink common channel; verifying whether there is a conflict between the first link scheduling time of the user equipment and the second link scheduling time corresponding to the time allocation information based on the time allocation information and the round-trip delay information includes: Obtain the common channel scheduling information of the downlink; Based on the common channel scheduling information of the downlink and the round-trip delay information, verify whether there is a conflict between the time when the user equipment initiates the uplink corresponding to the target time and the time when the user equipment schedules the downlink common channel; Correspondingly, if not, scheduling the uplink and downlink at the target time includes: If not, schedule the uplink at the target time.

8. The method according to claim 7, wherein The round-trip delay information includes the first time delay of the user equipment near the sub-satellite point and the second time delay of the far sub-satellite point; verifying whether there is a conflict between the time when the user equipment initiates the uplink corresponding to the target time and the time when the user equipment schedules the downlink common channel based on the common channel scheduling information of the downlink and the round-trip delay information includes: Obtain the time slot offset parameter, and determine the actual uplink scheduling time based on the timing offset parameter and the target time; In the scheduling status index table, determine a second verification interval based on the actual scheduling time, the first time delay, and the second time delay, where the second verification interval represents a potential conflict interval between the time when the user equipment initiates the uplink and the time when the user equipment schedules the downlink common channel; Check whether there is a flag bit representing an existing downlink common channel scheduling within the verification interval; Correspondingly, if not, scheduling the uplink at the target time includes; If there is no flag bit within the second verification interval, schedule the uplink at the target time.

9. The method according to claim 1, characterized in that, It further includes: Update the service area information of the satellite at preset intervals; Update the round-trip delay information based on the updated service area information of the satellite.

10. An uplink and downlink scheduling device, characterized in that, Applied to a base station, the base station is deployed on a satellite and includes: A calculation module configured to calculate the round-trip delay information between the satellite and the user equipment based on the service area information of the satellite; A verification module, configured to verify whether there is a conflict between a first link scheduling time of the user equipment and a second link scheduling time corresponding to the time allocation information based on the time allocation information and the round-trip delay information, where the first link scheduling time and the second link scheduling time are determined under the constraint of performing link scheduling at a target time; A scheduling module, configured to, if not, schedule the uplink and downlink at the target time, where the time allocation information is used to represent the time when the user equipment performs a scheduling task.

11. A computing device, characterized in that, Comprising: A memory and a processor; The memory is used to store computer programs / instructions, and the processor is used to execute the computer programs / instructions. When the computer programs / instructions are executed by the processor, the steps of the uplink and downlink scheduling method according to any one of claims 1-9 are implemented.

12. A computer-readable storage medium, characterized in that, It stores computer programs / instructions, and when the computer programs / instructions are executed by the processor, the steps of the uplink and downlink scheduling method according to any one of claims 1-9 are implemented.

13. A computer program product, characterized in that, Comprising computer programs / instructions, and when the computer programs / instructions are executed by the processor, the steps of the uplink and downlink scheduling method according to any one of claims 1-9 are implemented.

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